[Libguestfs] [PATCH libnbd] copy: Set POSIX_FADV_SEQUENTIAL and POSIX_FADV_DONTNEED.

[Richard W.M. Jones]

On Fri, Feb 19, 2021 at 09:36:58PM +0000, Richard W.M. Jones wrote:
> BTW it's extremely hairy, racy and probably slow, but it seems
> possible using mmap + mincore to determine which pages are resident,
> and so in theory avoid using POSIX_FADV_DONTNEED for those pages.

As described here:

https://insights.oetiker.ch/linux/fadvise/

Rich.

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